Nancy Guthrie Case Update: Why DNA evidence analysis at FBI lab taking so long? DNA expert Tiffany Roy explains the delay

Nancy Guthrie Update: Nearly 110 days have passed since the disappearance of Nancy Guthrie, the 84-year-old mother of Today show host Savannah Guthrie, from her Tucson, Arizona, home. Despite hundreds of leads and rewards offered by the Guthrie family and federal authorities, investigators, including the FBI, are still scrambling to identify or arrest a suspect.

DNA evidence collected during the investigation has become a central focus, sparking tensions between local authorities and federal agents. The rift surfaced publicly when FBI Director Kash Patel accused Sheriff Nanos’ department of failing to cooperate with the bureau during the early stages of the case.

In April 2026, media reports revealed that the FBI had received and was analyzing potentially critical DNA evidence recovered months earlier from Nancy Guthrie’s Tucson, Arizona, home. The sample, initially processed by a private Florida laboratory working with the Pima County Sheriff’s Department, was sent to the FBI in recent weeks, underscoring the federal agency’s involvement in examining evidence that could prove pivotal in the ongoing investigation.


As the search for Nancy Guthrie stretches on, forensic DNA expert Tiffany Roy joined Anne Emerson on the Criminally Obsessed podcast to address lingering questions about the investigation and the role of DNA evidence. Roy has processed thousands of DNA samples and worked on thousands of cases. Roy's job involves reviewing cases processed by private and government labs to ensure adherence to all procedures.

Responding to the query of why DNA evidence collected during the investigation and being analyzed by the FBI’s lab in Quantico is taking so long, Roy said, “There have been five different laboratories that have been involved in different stages of the testing of these samples. Um, and so what happens when you have a case where you have DNA but you don't know who it belongs to and you've searched it through the database, and we're using all the tools at our disposal to try to put a name with that piece of evidence.”

"…that can be very time-consuming, especially if they're in the genealogy process and if they have a sample that's suitable for genealogy…I know that they've discussed a mixed sample. Um, and sometimes mixed samples are not going to be helpful for genealogy, but it's the building of the trees and doing the research and working back through people's genetic lines to try to link it with a family name and ultimately the name of an actual person. So, that research takes the longest time,” she added.

FBI vs Chris Nanos

Recently, an apparent rift between Pima County Sheriff Chris Nanos and the federal probe agency investigating Guthrie’s disappearance surfaced publicly when FBI Director Kash Patel accused Sheriff Nanos’ department of failing to cooperate with the bureau during the early stages of the case.

FBI Director Patel emphasized the agency’s readiness to take charge of the DNA evidence found during the investigation, stating, “What we, the FBI, do is say, 'Hey, we’re here to help. What do you need? What can we do?’” Patel said on the Hang Out with Sean Hannity podcast on May 6, 2026, further stating that earlier involvement could have allowed the FBI to recover more evidence more quickly. “And for four days, we were kept out of the investigation.”

Nanos denied the allegation, stating that coordination between his officers and the FBI began soon after Nancy’s disappearance. “Director Patel has the right to his opinions,” he said, adding that he believed some of the remarks were “factually inaccurate.” “The FBI was with us from day one,” Nanos emphasized. “We’ve always had a working relationship.”

He also dismissed claims that investigators mishandled the crime scene or delayed search efforts during the critical early hours after Guthrie vanished. “The plane was started immediately,” Nanos said, referring to aerial search operations. “They found blood. Search and rescue looked at the scene and realized it seemed suspicious. They did exactly what they were supposed to do.”

Nancy vanished from her home in Tucson, Arizona, on January 31, 2026, and was reported missing by her family the next day. Following reports of her disappearance, the Pima County Sheriff’s Office launched an intense search effort, later joined by the FBI. Despite extensive investigation, Nancy has remained missing for more than four months, and despite hundreds of leads, no suspect has been caught or arrested to date.